So what's your opinion - do you think the overheating is unrelated to the water pump being replaced? Just coincidence? Doesn't help matters that we had the hottest day ever, for any day ever, in Atlanta this past week -- 106 degrees Fahrenheit.

 

Will definitely be doing this tomorrow.

 

At idle, there will be enough flow through an obstructed radiator, but at higher speeds, not so much so. If system has nnot been cleaned out in recent years, this may be something to look at as well.

 

Had it "flushed" last summer using a fluid replacement system at an oil change dealer. What's the best way to flush it? I haven't done this myself in years. We used to disconnect and reconnect the lower hose over and over while running the garden hose into the top. Don't suppose this is the proper method... Read on another thread that there is a (garden?) hose flush/drain outlet on bottom of radiator, but all I see are what I believe to be two transmission coolant lines, and a small drain ****.

 

ps. thanks for the replies

 

i'd start at the beginning with a suspicion of water pump and t-stat, and prove everything out one step at a time. since the overheating began immediately after the water pump replacement, i'd suspect something related to that.

somewhere in this thread or another, someone suggested checking that the belt was on correctly and not somehow routed backwards. that's good advice. also remove the belt from the tensioner and spin the water pump pulley and make sure the pump is turning. my experience with no water pump turning is that it overheats immediately, even at idle.

yes, you can remove the t-stat w/o removing AC, provided that the bolts don't break. its tight, but leave the hose attached to the t-stat housing to use as a handle to pull it out.

don't let it overheat, as that will cause head gaskets to fail and more over-heating.

 

Drain is on drivers side. You can hook a bit of 3/8ths (I think) line to it so it drains where you want it, instead of running all over.

When they did the water pump, (I am assuming you had a garage do that??) did they replace the stat as well? Check your receipt. If they did, go visit them, and they should fix it for you.

 

.....

 

Ah. Didn't catch that. (didn't reread the whole thing. )

 

Finally drained radiator today on this 2000 3.9l/75,000 miles, and shocked to see it full of crystals and sludge. Twice in the past 36 months I had flushed. This looks like solder bloom/blossoming. Is this caused by an electrical charge in cooling system? Should I beef up the ground or does cause of it need to be properly diagnosed, too?

So I'm going to install a new radiator, 180 degree t-stat, hoses, and radiator cap. Should I be thinking about replacing heater core, too? Is it likely full of bloom, too, and if so will it just reinfect the system?

Also, any suggestions on best radiator to install?